{"cve":"CVE-2025-40306","nvd":{"published":"2025-12-08T01:16:02.820","modified":"2026-10-14T22:10:00.210","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\norangefs: fix xattr related buffer overflow...\n\nWilly Tarreau <w@1wt.eu> forwarded me a message from\nDisclosure <disclosure@aisle.com> with the following\nwarning:\n\n> The helper `xattr_key()` uses the pointer variable in the loop condition\n> rather than dereferencing it. As `key` is incremented, it remains non-NULL\n> (until it runs into unmapped memory), so the loop does not terminate on\n> valid C strings and will walk memory indefinitely, consuming CPU or hanging\n> the thread.\n\nI easily reproduced this with setfattr and getfattr, causing a kernel\noops, hung user processes and corrupted orangefs files. Disclosure\nsent along a diff (not a patch) with a suggested fix, which I based\nthis patch on.\n\nAfter xattr_key started working right, xfstest generic/069 exposed an\nxattr related memory leak that lead to OOM. xattr_key returns\na hashed key.  When adding xattrs to the orangefs xattr cache, orangefs\nused hash_add, a kernel hashing macro. hash_add also hashes the key using\nhash_log which resulted in additions to the xattr cache going to the wrong\nhash bucket. generic/069 tortures a single file and orangefs does a\ngetattr for the xattr \"security.capability\" every time. Orangefs\nnegative caches on xattrs which includes a kmalloc. Since adds to the\nxattr cache were going to the wrong bucket, every getattr for\n\"security.capability\" resulted in another kmalloc, none of which were\never freed.\n\nI changed the two uses of hash_add to hlist_add_head instead\nand the memory leak ceased and generic/069 quit throwing furniture.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/025e880759c279ec64d0f754fe65bf45961da864","https://git.kernel.org/stable/c/15afebb9597449c444801d1ff0b8d8b311f950ab","https://git.kernel.org/stable/c/9127d1e90c90e5960c8bc72a4ce2c209691a7021","https://git.kernel.org/stable/c/bc812574de633cf9a9ad6974490e45f6a4bb5126","https://git.kernel.org/stable/c/c2ca015ac109fd743fdde27933d59dc5ad46658e"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2025-40306","score":0.00161,"percentile":0.05194,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}